Catálogo de publicaciones - revistas

<jats:title>Stem cells reshape a lymphatic niche</jats:title> <jats:p> Adult stem cells can both self-renew and regenerate new tissue upon demand. They reside in microenvironments (niches) that balance these decisions to avoid tissue overgrowth, cancer, and aging. Using murine skin as a model, Gur-Cohen <jats:italic>et al.</jats:italic> uncovered a lymphatic network of capillaries associated with the stem cell niche of hair follicles (see the Perspective by Harvey). Stem cells reshaped their lymphatic environment by switching their secretome to coordinate lymphatic-niche association. During tissue regeneration, a dynamic change in epithelial-lymphatic communication remodeled this association, synchronizing stem cell and niche behavior. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6470" page="1218" related-article-type="in-this-issue" vol="366" xlink:href="10.1126/science.aay4509">1218</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6470" page="1193" related-article-type="in-this-issue" vol="366" xlink:href="10.1126/science.aaz8780">1193</jats:related-article> </jats:p>

<jats:title>Divacancies in a diode</jats:title> <jats:p> Solid-state defects hold great promise as the building blocks for quantum computers. Most research has focused on defects in diamond, which are difficult to integrate with existing semiconductor technologies. An alternative two-vacancy neutral defect in silicon carbide (SiC) has a long coherence time but suffers from broad optical linewidths and charge instability. Anderson <jats:italic>et al.</jats:italic> fabricated these defects in a diode made out of commercially available SiC. Reverse voltage created large electric fields within the diode, tuning the frequencies of the defect's transitions by hundreds of gigahertz. The electric fields also caused charge depletion, leading to a dramatic narrowing of the transitions. The technique should be readily generalizable to other quantum defects. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6470" page="1225" related-article-type="in-this-issue" vol="366" xlink:href="10.1126/science.aax9406">1225</jats:related-article> </jats:p>

<jats:title>A timely look into electron-phonon coupling</jats:title> <jats:p> The coupling between electrons and phonons—lattice vibrations in solids—is responsible for macroscopic quantum phenomena such as superconductivity. Yet, experimentally measuring this coupling as a function of momentum and for a particular phonon mode is tricky. Na <jats:italic>et al.</jats:italic> used time- and angle-resolved photoemission spectroscopy to excite electrons in graphite and monitor their decay, which was accompanied by the release of phonons. The time constants of these decay processes provided direct information on electron-phonon couplings in this system. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6470" page="1231" related-article-type="in-this-issue" vol="366" xlink:href="10.1126/science.aaw1662">1231</jats:related-article> </jats:p>

<jats:title>Vulnerability to habitat fragmentation</jats:title> <jats:p> Habitat fragmentation caused by human activities has consequences for the distribution and movement of organisms. Betts <jats:italic>et al.</jats:italic> present a global analysis of how exposure to habitat fragmentation affects the composition of ecological communities (see the Perspective by Hargreaves). In a dataset consisting of 4489 animal species, regions that historically experienced little disturbance tended to harbor a higher proportion of species vulnerable to fragmentation. Species in more frequently disturbed regions were more resilient. High-latitude areas historically experienced more disturbance and harbor more resilient species, which suggests that extinction has removed fragmentation-sensitive species. Thus, conservation efforts to limit fragmentation are particularly important in the tropics. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6470" page="1236" related-article-type="in-this-issue" vol="366" xlink:href="10.1126/science.aax9387">1236</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6470" page="1196" related-article-type="in-this-issue" vol="366" xlink:href="10.1126/science.aba1103">1196</jats:related-article> </jats:p>

<jats:title>Tracking excitations</jats:title> <jats:p> Illumination can be used to excite a sample from its ground state to a number of excited states. Typically, however, the details of the excitation dynamics are hidden from view because they decay so fast. Piatkowski <jats:italic>et al.</jats:italic> combined pump-probe transient absorption and two-pulse photoluminescence correlation spectroscopy, allowing them to assess stimulated emission and ground-state bleaching contributions to the transient absorption signal. This approach provides a window on the excitation dynamics within single nanocrystals and should also be useful for ultrafast nanocharacterization of complex samples. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6470" page="1240" related-article-type="in-this-issue" vol="366" xlink:href="10.1126/science.aay1821">1240</jats:related-article> </jats:p>

<jats:title>Transmitting quantum states</jats:title> <jats:p> The coherence of electrons in mesoscopic structures is thought to be unlikely to survive in a disordered environment. Duprez <jats:italic>et al.</jats:italic> show that this is not necessarily the case. They studied a metallic island as an example of a disordered environment. They made an electron interferometer and incorporated the island in one of the two paths through the interferometer. At sufficiently low temperatures and in the quantum Hall regime, they observed a clear interference pattern, indicating successful transmission of the electrons' quantum state across the island. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6470" page="1243" related-article-type="in-this-issue" vol="366" xlink:href="10.1126/science.aaw7856">1243</jats:related-article> </jats:p>

<jats:title>A childhood tumor—from the beginning</jats:title> <jats:p> Many adult cancers arise from clonal expansions of mutant cells in normal tissue. These premalignant expansions are defined by somatic mutations shared by the cancers. Whether pediatric cancers originate in a similar way is unknown. Coorens <jats:italic>et al.</jats:italic> studied Wilms tumor, a childhood kidney cancer. Phylogenetic analyses revealed large clones of mutant cells in histologically and functionally normal kidney tissue long before tumor development. Thus, like adult tumors, Wilms tumor appears to arise from a premalignant tissue bed. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6470" page="1247" related-article-type="in-this-issue" vol="366" xlink:href="10.1126/science.aax1323">1247</jats:related-article> </jats:p>

<jats:title>Sensing light without forming images</jats:title> <jats:p> In the rodent retina, intrinsically photosensitive retinal ganglion cells (ipRGCs) entrain circadian rhythms, modulate mood, and signal pupillary accommodation. Such responses are light-driven but not image-based. Working with donated human organ tissues, Mure <jats:italic>et al.</jats:italic> used electrophysiological approaches to identify ipRGCs in the human retina. The human retina has more cones than the retinas of nocturnal mice and rats. Differences in sensitivity, latency, and duration of responses identified three subtypes of human ipRGCs. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6470" page="1251" related-article-type="in-this-issue" vol="366" xlink:href="10.1126/science.aaz0898">1251</jats:related-article> </jats:p>